Fix wxUSE_GRAPHICS_DIRECT2D definition in setup.h files.

Define it in wx/msw/setup_inc.h and not in wx/msw/setup0.h itself to ensure
that it survives the regeneration of this file using build/update-setup-h.

Also only set wxUSE_GRAPHICS_DIRECT2D to 1 for VC10+ and not VC9 as the latter
lacks Direct2D header in its default SDK version.

Finally also update comments to explain the various settings more clearly and
remove outdated information (wxGraphicsContext is not experimental any more).

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@77669 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/android/setup.h

@@ -727,19 +727,14 @@
 #define wxUSE_WEBVIEW_WEBKIT 0
 #endif
 
-// Enable the new wxGraphicsPath and wxGraphicsContext classes for an advanced
-// 2D drawing API.  (Still somewhat experimental)
-//
-// Please note that on Windows gdiplus.dll is loaded dynamically which means
-// that nothing special needs to be done as long as you don't use
-// wxGraphicsContext at all or only use it on XP and later systems but you
-// still do need to distribute it yourself for an application using
-// wxGraphicsContext to be runnable on pre-XP systems.
+// Enable wxGraphicsContext and related classes for a modern 2D drawing API.
 //
 // Default is 1 except if you're using a non-Microsoft compiler under Windows
-// as only MSVC7+ is known to ship with gdiplus.h. For other compilers (e.g.
-// mingw32) you may need to install the headers (and just the headers)
-// yourself. If you do, change the setting below manually.
+// as only MSVC is known to ship with at least gdiplus.h which is required to
+// compile GDI+-based implementation of wxGraphicsContext (MSVC10 and later
+// versions also include d2d1.h required for Direct2D-based implementation).
+// For other compilers (e.g. mingw32) you may need to install the headers (and
+// just the headers) yourself. If you do, change the setting below manually.
 //
 // Recommended setting: 1 if supported by the compilation environment